The agreement comes months after a similar deal between Rosneft and BP collapsed when BP could not reach a deal with shareholders of a Russian affiliate, TNK-BP. (A suit against BP, brought by TNK-BP, is proceeding in regional court in Western Siberia.) Skadden international arbitration partner David Kavanagh and global transactions cohead Scott Simpson led a Skadden team that represented the TNK-BP shareholders on that deal.

Skadden was engaged on oil-field development again, this time by Exxon Mobil, which hired the firm to represent it on the deal with Rosneft. Skadden energy and infrastructure projects partners Julia Czarniak and Harold Moore led the firm's efforts. Exxon Mobil was also advised by an Akin Gump team that was led by international corporate transactions partners Richard Wilkie and Alexey Kondratchik, both in Moscow, and included corporate partner Douglas Glass, in London and corporate counsel Svetlana Volevich, in Moscow. S. Jack Balagia, Jr., is Exxon Mobil's general counsel.

Rosneft is represented by a team from Freshfields led by corporate partner Frank Miller, in London and corporate partner Sergei Diyachenko, in Moscow. Miller and Diyachenko previously advised Rosneft on the now-defunct agreement with BP. Freshfields previously advised Rosneft on an earlier $1 billion agreement with Exxon Mobil. That deal between Exxon Mobil and Rosneft also concerned Black Sea oil exploration.

Larisa Kalanda is Rosneft's vice president for legal support and also serves as deputy chairman of the company's management board.